Temperature control system



Dec. 26, 1939- c. B. SPANGENBERG TEMPERATURE CONTROL SYSTEM Filed Feb. 13, 1936 fionyealeg Il/a' ATTOENEX Patented Dec. 26, 1939 UNITED STATES TEMPERATURE CONTROL SYSTEM Charles B. Spangenberg, Minneapolis, Minn., as-

signor to Minneapolis-Honeywell Regulator Company, Delaware Minneapolis, Minn.,. av corporation of Application February 13, 1936, Serial No. 63,726

11 Claims.

if the building heating means is started at a given time each morning the temperature of the building will'be restored to the normal value later on severe mornings than on mild mornings.

It is the prime object of this invention to provide a temperature control system wherein the building temperature is restored to normal at a 2 given time each morning regardless of outdoor atmospheric conditions.

More specifically, it is an object of this invention to provide a means for starting the building heating means earlier when the outdoor atmospheric conditions are severe and later when the outdoor atmospheric conditions are mild, in order to restore the building temperature to normal at a given time each morning.

In carrying out my invention I utilize a mass 30 located outside of the building, which is maintained at a given temperature greater than the ambient temperature. At a given time in the morning the mass is allowed to cool and the rate of cooling of the mass is determined by the severity of the outdoor atmospheric conditions.

On severe mornings the mass will coolmuch more rapidly than on mild mornings, and this rate' of cooling is not only determined by the outdoor, temperature but by the combined effects 40 of the outdoor temperature, wind and solar radiation. A thermostatic device responsive tothe temperature of the mass is operable when the temperature of the mass has cooled to a given I have shown my invention as applied to a temperature control system of the type shown and described in application Serial No. 512,887 filed by Daniel G. Taylor on February 2, 1931 and which has matured into Patent No. 2,065,835 issued December 29, 1936. The system disclosed in this Taylor application comprises an outdoor controller responsive to outdoor atmospheric conditions, including temperature, wind and solar radiation, for controlling the temperature within the building. Heating means are provided in the building for supplying heat to the building, and heating means are also provided in the outdoor controller for supplying heat to the outdoor controller. The two heating means are proportioned according to the'heat losses from the buildingand from the outdoor controller. A thermostatic device is provided for responding to the temperature within the outdoor controller and when this thermostatic device calls for heat both of the heating means are energized to deliver heat to the building and to the outdoor controller. Due to the proportional relationship of the heating means with the heat losses of the building and the outdoor controller a definite temperature relation is maintained within the building and the outdoor controller, so that by responding to the temperature of the outdoor controller the thermostatic device maintains a constant or normal temperature within the building.

Such a system gives accurate results when the system 'is maintained in operation for twentyfour hours a day. However, it is often desirable to shut down the heating system during the night to lower the temperature within the building to conserve on fuel costs, but due to the fundamental theory of operation the system of the Taylor application cannot supply suflicient heat to the building in the morning after a night shutdown to rapidly raise the temperature to normal and thereafter maintain the temperature in the building at normal. This is caused by the fact that only sufficient heat is supplied to the building to maintain the temperature thereof constant according to variationsin outside atmospheric conditions. In order to successfully operate a system of the type disclosed in the above referred to Taylor application where it is desired to have a night shutdown, it is necessary that some independentmeans be provided to raise the temperature in the building to normal after a night shutdown.

Therefore, it is another object of this invention to provide a. morning pickup control for this type of heating system, whereby the building temperature is brought up to normal so that the temperature of the building may be maintained at normal by the outdoor controller.

In carrying out this portion of my invention I provide means for continuously operating the building heating means independent of the outdoor controller to restore the building temperature to normal, and the period of time during which the building heating means is continuously operated is determined by the above referred to variable morning pickup outdoor controller. In other words, the morning pickup controller is allowed to cool at a given time in he morning and when the morning pickup controller has cooled to a predetermined value the building heating means is placed in continuous operation until a subsequent time in the morning when the building heating means is placed under the control of the outdoor controller of the above referred to Taylor application. Therefore, the beginning of the period of continuous operation of the building heating means will vary in accordance with outdoor atmospheric conditions so that the building temperature will be restored to normal at a given time each morning regardless of outdoor atmospheric conditions, and when the building temperature is so restored the control of the building heating means is transferred to the outdoor controller of the Taylor application. The structure and mode of operation of this portion of my invention also form objects of my invention.

Other objects and advantages will become apparent to those skilled in the art upon reference to the accompanying specification, claims and drawing.

The single sheet of the drawing illustrates the preferred form of my invention.

Referring now to the drawing, I have shown a building having a side wall 9 and a plurality of spaces H! to be heated. Located in each space I9 is a heat exchanger or radiator II which receives a supply of heating fluid, such as hot water, through risers 2 connected to a header 3 which in turn is connected by a pipe l4 to a boiler l5. The boiler I5 is heated by means of an oil burner l6 having the usual safety controls, not shown. Water is returned from the radiators H by means of pipes H to a header l8 connected into the boiler l5. By reason of these piping connections hot water is circulated from the boiler I5 through the radiators H to cause lgaating of the spaces I0.

An outdoor controller located outside of the building is generally designated at 20. This outdoor controller 20 may comprise amass in the form of a metallic block 2| which may be heated by an electric heating element 22. The block 2| is cooled by the ambient atmospheric conditions, including temperature, wind and solar radiation. The block 2| is hollowed out to receive a container 23 in which is mounted a bimetallic element 24 by means of a post 25. The bimetallic element 24 operates contacts 26 and 21 which are adapted to sequentially engage contacts 28 and 29 respectively. The container 23 is provided with a cover 38 so that the bimetallic element 24 responds directly to the temperature of the metallic block 2|. The arrangement is such that as the block temperature decreases to 72, contacts 26 and 28 are made and upon a further decrease in temperature to 68 the contacts 21 and 29 are made. The component parts of the outdoor controller 28 may be housed in a suitable casing 3| to protect the same against the elements.

Line wires leading from some source of power, not shown, are designated at 33'and 34. A primary 35 of a step-down transformer 36 having a secondary 31 is connected across the line wires 33 and 34. A relay coil 38 controls the operation of switch arms 39, 40 and 4| with respect to contacts 42, 43 and 44 respectively. The arrangement is such that when the relay coil 38 is energized the switch arms 39, 48 and 4| are moved into engagement with the contacts 42, 43 and 44 and when the relay coil 38 is deenergized the switch arms are moved out of engagement with their respective contacts by means of springs, gravity or other means, not shown. One end of the secondary 31 is connected by a wire 45 to one end of the relay coil 38. The other end of the secondary 31 is connected by a wire 46 to the contact 28 of the outdoor controller 28. The contact 29 is connected by wire 41 to the other end of the relay coil 38. The bimetallic element 24 is connected by a wire 48 to the contact 42 and the switch arm cooperating therewith is connected by a wire 49 to the junction of wire 41 and the relay coil 38. The contact 43 is connected by a wire 5| to the line wire 34 and the switch arm 48 cooperating therewith is connected by a wire 52, a variable resistance 53 and wire 54 to one end of the electric heating element The other end thereof is connected by a wire 55 to the line wire 33.

As the block temperature decreases to 72 due to the outdoor atmospheric conditions contacts 26 and 28 are made, and when the block temperature decreases to 68 contacts 21 and 29 are made. This completes a. circuit from the secondary 31 through wire 46, contacts 28, 26, 21 and 29, wire 41, relay coil 38 and wire 45 back to the secondary 31. Completion of this circuit causes energization of the relay 001138 to move the switch arms 39, 40 and 4| into engagement with the contacts 42, 43 and 44 respectively. Movement of the switch arm 39 into engagement with the contact 42 completes a maintaining circuit for the relay coil 38 from the secondary 31 through wire 46, contacts 28 and 26, bimetallic element 24, wire 48, contact 42, switch arm 39, wire 49, relay coil 38 and wire 45 back to the secondary 31. Completion of this circuit maintains the relay coil 38 energized until such time as the block temperature shall rise to 72 to break contact between the contacts 26 and 28. Movement of the switch arm 48 into engagement with the contact 43 completes a circuit from the line wire 34 through wire 5|, contact 43, switch arm 40, wire 52, variable resistance 53, wire 54, electric heating element 22 and wire 55 back to the line wire 33. Therefore, when the relay coil 38 is energized the electric heating element 22 is energized to cause heating of the block 2| and the amount of heat delivered to the block 2| by the electric heating element 22 is controlled by the variable resistance 53 in circuit therewith. In this manner the block 2| is alternately heated and cooled to maintain the temperature thereof within the limits of 68 to 72".

This invention contemplates the use of a time switch generally designated at 51. The time switch may comprise a motor rotor 58 operated by afield winding 59 which is connected by wires 68 and 6| across a secondary 62 of a step- 75 down transformer 63 having a primary 64 connected across the line wires 33 and 34. Rotation of the motor rotor 58 is translated through a reduction gear train 65 to operate adjustable cams 66, 61 and 68, the arrangement being such that the cams 66, 6! and 68 make one revolution every 24 hours. 0am 66 operates a switch arm 68 with respect to a contact I0, the cam 6! a switch arm II with respect to a contact I2, and the cam 68 a switch arm I3 with respect to a contact I4. The cams 66, 61 and 68 are shaded to designate a. m. and p. m. portions, the p. m. portions being shaded. Since the cams are rotated in the direction indicated by the arrows it is seen that the cams are in a position corresponding to 12:00 midnight. It is seen that-the cam 68 will move the switch arm I3 into engagement with the contact I4 at substantially 7:00 a. m. and will move the switch arm I3 out of engagement with the contact I4 at substantially 11:00 p. m. The cam 61 will move the switch arm II into engagement with the contact I2 at substantially 5:00 a. m. and out of engagement therewith at 7:00 a. m. The

cam 66 will move the switch arm 68 into engagement with the contact I0 at 11:00 p. m. and out of engagement therewith at 5:00 a. m.

The contact 44 associated with the switch arm 4|, operated by the relay coil 38, is connected by a wire 11 to the line wire 34 and the switch arm 4| is connected by a wire I8 to the contact I4 of the time'switch. The switch arm I3 is connected by wires I8 and 80 to the oil burner I6 which in turn is connected by a wire 8| to the other line wire 33. Assume for the present that the time switch 51 is in position for day operation and that the switch arm I3 is in engagement with the contact I4. Upon a call for heat by the outdoor controller so as to energize the relay coil 38 the switch arm 4I' is moved into engagement with the contact 44 to complete a circuit from the line wire 34 through wire 11, contact 44, switch arm 4|, wire I8, contact I4, switch arm I3, wires I8 and 80, oil burner I6, and wire 8| back to the line wire 33. Completion of this circuit causesoperation of the oil burner I6 and consequent heating of the water inthe boiler I5 to supply heat to the spaces I0. In this manner the oil burner I6 is operated simultaneously with the electric heating element 22 by the thermostatic switching mechanism of the outdoor controller 20. By properly adjusting the variable resistance 53 to maintain the heat inputs to the outdoor controller 20 and to the spaces I0 proportional to the heat losses from the outdoor controller 20 and the spaces I0, the building temperature may be maintained constant throughout the day in the manner disclosed in the above referred to Taylor application.

In order to accomplish a variable morning pickup so that'the temperature of the building is restored to normal at a given time each morning following a night shutdown, I provide an outdoor controller generally designated at 83. This outdoor controller 83 may comprise a mass in v the form of a metallic block 84 which is heated vided with a cover 88 so that the bimetallic elements 81' and 88 are responsive solely to the temperature of the metallic block 84. The contacts 83 and 84 are so adjusted that when the block temperature decreases to 102 contacts 8I and 83 are made, and when the block temperature decreases to 100 the contacts 83 and 84 are made. The contacts 81 and 88 are so adjusted that when the temperature of the block 84 decreases to 62 the contacts 85 and 81 are made, and when the temperature decreases to 60 the contacts 86 and 88 are made. The component parts of the outdoor controller 83 may be enclosed in a suitable casing I00 to protect the same from the elements.

A relay coil I02 operates switch arms I03 and I04 with respect to contacts I05, I06 and I0I. The arrangement is such that when the relay coil I02 is energized the switch arms I03 and. I04 are moved into engagement with the contacts I05 and I06 and-when the relay coil I03 is deenergized the switch arms I03 and I04 are moved out of engagement with contacts I05 and I06, and the switch arm I04 is moved into engagement with the contact I0I by means of springs, gravity or other means, not shown. A primary I08 of a step-down transformer I08 having a secondary H0 is connected across the line wires 33 and 34.

One end of the secondary H0 is connected to one end of the relay coil I02 by a wire III. The other end of the secondary H0 is connected by a wire 2 to the contact I0 of the time switch 51. The switch arm 68 cooperating with the contact I0'is connected by a wire I I3 to the contact 83 of the outdoor controller 83. The contact 84 is connected by a wire "4 to the other end of the relay coil I02. The bimetallic element 81 is connected by a wire -I I5 to the contact I05 and the switch arm I03 is connected by a wire II6 to the junction of the wire "4 and the relay coil I02. The -line wire 34 is connected by a variable resistance H8 and a wire II8 to the contact I06 and the switch arm I04 cooperating therewith is connected by a wire I20 to one end of the electric heating element 85. The other end thereof is connected by a wire I2I to the line wire 33. The line wire 34 is connected by a variable resistance I22 and a wire I23 to the contact I0I.

With the time switch 51 in a position corresponding to midnight asshown in the drawing, the switch arm 68 is held in engagement with the contact I0. When the temperature of the block 84 decreases to a circuit is completed from the secondary -I I0 through wire II 2, contact I0, switch arm 68, wire II3, contacts 83, 8|, 82 and 84, wire II4, relay coil I02 and wire III back to the secondary IIO. Completion of this circuit causes energization of the relay coil I02 to move the switch arms I03 and I04 into engagement with the contacts I05 and I06 respectively. Movement of the switch arm I03 into engagement with the contact I05 completes a maintaining circuit for the relay coil I 02 from the secondary IIO through wire II 2, contact I0, switch arm 68, wire II3, contacts 83 and 8|,- bimetallic element 81, wire II5, contact I05, switch arm I03; wire II6, relay coil "I02 and wire III back to the secondary IIO. This circuit main-- tains the relay coil I02 energized until such time as the block temperature shall rise to. 102. Movement of the switch arm I04 into engagement with the contact I06 completes a circuit through the variable resistance 8 to cause energization of the electric heating element 85 to heat the block 84 to restore the temperature of the block to 102. The variable resistance II8 may be adjusted to vary the rate at which the block 84 is heated. When the temperature of the block 84 reaches 102 the relay coil I02 is deenergized to move the switch arm I04 into engagement with the contact I01. This completes a circuit from the line wire 34 through variable resistance I22, wire I23, contact I01, switch arm I04, wire I20, heating element and wire I2I back to the other line wire 33. The variable resistance I22 is provided in this circuit to supply a small amount of heat to the heating element 85 when the block 84 is being cooled by the outdoor atmospheric conditions. The amount of heat supplied to the heating element 85 through the variable resistance I22 is not suflicient to raise or maintain the temperature of the block 84 but only provides a retarding effect on the cooling of the block 84. When the time switch 51 moves the switch arm 69 out of engagement with the contact 10 the relay coil I02 is deenergized and it is impossible to energize the same even though the bimetallic element 81 of the outdoor controller 83 should be calling for heat. Therefore, when the time switch moves the switch arm 69 out of engagement with the contact 10 the block 84 is allowed to cool down to ambient atmospheric conditions and the rate of cooling of the block 84 is dependent upon outdoor atmospheric conditions, including temperature, wind and solar radiation, and the heating effect of the heater 85 as influenced by the variable resistance I22. For given outdoor atmospheric conditions the rate of cooling of the block 84 may therefore be adjusted by adjustment of the variable resistance I212. It follows, then, that with a given adjustment of the variable resistance I22 the block 84 will cool more rapidly when the outdoor atmospheric conditions are severe and less rapidly when the outdoor atmospheric conditions are mild.

A relay coil I25 operates switch arms I26 and I21 with respect to contacts I28 and I29, the arrangement being such that when the relay coil I25 is energized switch arms I26 and I21 are moved into engagement with the contacts I28 and I 29 respectively, and when the relay coil I25 is deenergized the switch arms I26 and I21 are moved out of engagement with their respective contacts by means of springs, gravity or other means, not shown. A primary I30 of a step-down transformer I3I having a secondary I 32 is connected across the line wires 33 and 34. One end of the secondary I32 is connected by a wire I33 to one end of the relay coil I25 and the other end of the secondary I32 is connected by a wire I34 to the contact 91 of the outdoor controller 83. Contact 98 is connected by a wire I35 to the other end of the relay coil I25. *The bimetallic element 88 is connected by a wire I36 to the contact I 28 and the switch arm I26 cooperating therewith is connected by a wire I 31 to the junction of wire I35 and the relay coil I25.

When the temperature of the block 84 decreases to 60 the contacts 95, 96, 91 and 98 are made and a circuit is completed from the secondary I32 through wire I34, contacts 91, 95, 9s aha 98, wire I35, relay coil I25 and wire I 33 back to the secondary I32. Completion of this circuit causes energization of the relay coil I25 to move the switch arms I26 and I 21 into engagement with the contacts I28 and I29 Movement of the switch arm I26 into engagement with the contact I 28 completes a maintaining circuit for the relay coil I25 from the secondary I32 through .wire I34, contacts 91 and 95, bimetallic element 88, wire I36, contact I28, switch arm I26, wire I31, relay coil I25 and wire I33 back to the secondary I32. Completion of this circuit maintains the relay coil I25 energized until such time as the temperature of the block 84 shall rise above 62.

Line wire 34 is connected by wires 11 and I38 to the contact 12 of the time switch 51. The switch arm 1! cooperating with the contact 12 is connected by a wire I39 to the contact I29, and the switch arm I21 cooperating therewith is connected by wire I40 to the junction of wires 19 and 80. Therefore; when the relay coil I 25 is energized and the time switch 51 is in such position as to cause engagement of the switch arm H with the contact 12 a circuit is completed from the line wire 34 through wires 11 and I38, contact 12, switch arm II, wire I39, contact I29, switch arm I21, wires I40 and 80, oil burner I6 and wire 8I back to the other line wire 33, to cause operation of the oil burner I6.

Summarizing the operation of the entire system, it is assumed that the parts are in the position shown in the drawing and that the time switch corresponds to 12:00 midnight. The heater 22 of the outdoor controller 20 is alternately energized and deenergized whereby the temperature of the block 2I of the outdoor controller 20 is maintained within temperature limits of 68 and 72. Since at 12:00 oclock the time switch arm 13 is out of engagement with the contact 14 the operation of the outdoor controller 20 does not cause operation of the oil burner I6.

Likewise, since the switch 1| is out of engagement withthe contact 12 the oil burner I6 cannot be placed in operation independently of the relay controlled by the outdoor controller 20. Therefore, the supply of heat to the building is shut off and the building temperature is allowed to deviate from normal. The switch arm 69 of the time switch 51 is maintained in engagement with the contacts 10, and therefore the heating means 85 of the outdoor controller 83 is alternately energized and deenergized to maintain the temperature of the block 84 of the outdoor controller 83 between the limits of and 102.

At 5:00 oclock in the morning the cam 61 of the time switch 51 moves the switch arm 1I into engagement with the contact 12 but the oil burner is not immediately placed in operation since the switch arm I 21 is out of engagement with the contact I29 by reason of the temperature of the block 84 being above 60. Also, at 5:00 oclock in the morning the switch arm 69 of the time switch 51 is moved out of engagement with the contact 10 to deenergize the relay coil I02 whereby the block 84 of the outdoor controller 83 is allowed to cool, the rate of cooling being dependent upon the adjustment of the variable resistance I22 and upon outdoor atmospheric conditions, including temperature, wind, and solar radiation. When the block 84 of the outdoor controller 83 cools to 60 the relay coil I25 is energized to move the switch arm I21 into engagement with the contact I29 to complete a circuit therethrough and through the switch arm H and contact 12 of the time switch 51 to the oil burner I6 to cause operation thereof. Operation of the oil burner I6 in this manner causes continuous supply of heat to the spaces I0 of the building.

At 7:00 o'clock in the morning the switch arm H of the time switch 51 is moved out of engagement with the contact 12 to stop continuous operation of the oil burner I6 since at that time the building temperature is restored to normal. Also at 7:00 oclock in the morning the switch arm 13 is moved into engagement with the contact 74 to place the control of the oil burner l6 under the outdoor controller 20, and in the manner pointed out above, the outdoor controller 20 controls the oil burner Hi to supply sufficient heat to the building to maintainthe temperature of the building constant throughout the day.

At 11:00 oclock in the evening the switch arm 13 of the time switch 51 is moved out of engagement with the contact I4 to take the control of the oil burner l6 away from the outdoor controller 20, whereby the building temperature is allowed to deviate from normal. Also at 11:00 o'clock in the evening the switch arm 69 is moved int engagement with the contact 10 to cause heating of the block 84 of the outdoor controller 83 to substantially 100 and the above cycle of operation is repeated.

From the above description of operation it is seen that the supply of heat to the outdoor controller 83 is decreased at a given time in the morning, 5:00 oclock as illustrated. When the temperature of the block 84 decreases to a given value, 60 as illustrated, the oil burner I6 is placed in continuous operation. For purposes of illustration it is assumed that continuous operation of the oil burner l6 during the severest weather conditions for an hour and a half will restore the building temperature to normal. Since the time period of the cam 6'! is two hours,

, .the variable resistance I22 which regulates the cooling rate ofthe block 84 is so adjustedthat under the severest weather conditions it will take one-half an hour for the block 84 to cool from 100 down to 60; It follows then that for the two-hour timing period controlled by the cam 61 of the time switch 51, one-half an hour is utilized for cooling the block 84 and one hour and a half of continuous operation of the oil burner I6 is utilized for heating the building. Therefore, the building temperature is restored to normal during this morning pickup cycle. When the outdoor atmospheric conditions are relatively mild, it takes only one-half an hour to heat the building to restore the building temperature to normal, and it takes substantially one hour and a half for the block 84 to cool from 100 to 60 during these mild weather conditions. Therefore, during mild weather conditions the oil burner l6 will be turnedon at substantially 6:30 in the morning to restore the building temperature to normal at 7:00 oclock. For intermediate weather conditions the rate of heating of the building and the rate of cooling of the block 84 will vary inversely with respect to each other. It follows thenthat the oil burner I6 is placed in continuous operation at a time in the morning which varies in accordance with outdoor atmospheric conditions, so that regardless of the outdoor atmospheric conditions the building temperature is restored to normal at a given time in the morning, illustrated as 7:00 o'clock. Since the outdoor controller 83, performing the variable morning pickup cycle, is subject to the same ambient atmospheric conditions as the building, including temperature, wind, and solar radiation, the building temperature will be restored to normal at a given time each morning regardless of theeffects of temperature, wind or solar radiation.

Although I have disclosed my invention as applied to a heating system of the type shown and described in the above referred to Taylor application, it is applicable to other types of heating systems, such as a heating system using the conventional room thermostat. The various timing intervals and temperature values used throughout this specification are so used for purposes' of illustration only, since for various installations these timing values and temperature values may be different, and it is within the contemplation of this invention to use such timing and temperature values as will cause the satisfactory operation of the temperature control system. Although for purposes of illustration I have shown. one form of my invention, other forms thereof may become obvious to those skilled in the art and'consequently this invention is to be limited only by the scope of the appended claims and prior art.

I claim as my invention:

' 1. In a temperature control system for a building for providing a variable morning pickup following a night shutdown, the combination of heating means for the building, a controller maintained at a predetermined high temperature, time means operative at a given time in the morning to allow the controller to cool, thermostatic means responsive to the temperature of the controller for placing the heating means in operation when the controller temperature decreases to a given value to restore the building temperature to normal, and means for adjusting the rate of cooling of the controller.

2. In a temperature control system for a building for providing a variable morning pickup following a night shutdown, the combination of heating means for the building, a controller outside of the building and subject to the same ambient conditions as the building, said controller including temperature responsive means and heating means to maintain the temperature thereof at a given value above the ambient, time means operable at a given time in the morning to cause cooling of the controller, the thermostatic means .being operable at a given temperature of the controllerto place the building heating means in operation to restore the building temperature to normal, and means for adjusting the rate of cooling of the controller.

3. In a temperature control system for a building, the combination of heating means for the building, temperature responsive means in control of the heating means to maintain the building temperature at normal during the daytime, a controller outside of the building and subject to the same ambient conditions as the building and including thermostatic means responsive'to the temperature thereof andheating means to maintain the temperature thereof at a given value during the night,time means for interrupting the control of the building heating means by the temperature responsive means during the night whereby the building temperature is allowed to deviate from normal and for interrupting the supply of heat to the outdoor controller at a given time in the moming whereby the outdoor controller is allowed to cool, the thermostatic means placing the building heating means in operation when the temperature of the controller decreases to a given value whereby the building temperature is restored to normal, and the time means also placing the building heating means under the control of thetemperature responsive means at a subsequent time in the morning whereby the building temperature is maintained at normal.

4. In a temperature control system for a the building, temperature responsive means in control of the heating means to maintain the building temperature at normal duringthi daytime, a controller outside of the building and subject to the same ambient conditions as the building and including thermostatic means responsive to the temperature thereof and heating means to maintain the temperature thereoi at a given value during the night, time means for interrupting the control of the building heating means by the temperature responsive means during the night whereby the building temperature is allowed to deviate from normal and for interrupting the supply of heat to the outdoor controller at a given time in the morning whereby the outdoor controller is allowed to cool, the thermostatic means placing the building heating means in operation when the temperature of the controller decreases to a given value whereby the building temperature is restored to normal, and the time means also placing the building heating means under the control of the temperature responsive means at a subsequent time in the morning whereby the building temperature is maintained at normal, and means for adjusting the rate of cooling of the controller.

5. In a temperature control system for a building, the combination of heating means for the building, a first controller outside of the building responsive to the same. atmospheric conditions as the building including temperature, wind and solar radiation, for controlling the building heating means to maintain the building temperature constant throughout the day, means for interrupting the control of the building heating means by the outdoor controller during the night whereby the building temperature is allowed to deviate from normal, means controlling the building heating means to restore the temperature of the building to normal in the morning, and a second controller outside of the building responsive to the same atmospheric conditions as the building including temperature, wind and solar radiation for determining when the last mentioned means shall control said building heating means to restore the building temperature to normal.

6. In a system of the class described, the combination of a temperature changing means for a building, means for controlling said temperature changing means to maintain a normal temperature within the building, means for controlling the temperature changing means so that the building temperature may deviate from normal, and means for restoring said building temperature to normal, said last mentioned means including a controller influenced by outside weather conditions, a temperature changer for said controller, thermostatic means responsive to the temperature of the controller for controlling said controller temperature changer, timing means for placing said building temperature changer in operation to restore the building temperature to normal, and means influenced by the rate of heat loss from said controller for cooperating with said timing means to determine the time at which said temperature changer is operated to restore the building temperature to normal.

7. In a system of the class described, in combination, a condition changer for a space, a controller outside of said space, a condition changer ing said controller condition at a predetermined value, means for placing said condition responsive means out of operation to allow said controller condition to vary, and means influenced by the rate of variation in said controller condition for controlling said space condition changer.

8. In a system of the class described, the combination of heating means for a building, means for controlling the heating means to maintain the building temperature normal for a predetermined period and to permit the temperature to deviate from normal at the end of said period, means to control the heating means to cause the temperature to be restored to normal at a predetermined time, said last-mentioned means including an element capable of being heated, means causing said element to be heated to a maximum temperature during the time that the building temperature is permitted to deviate from normal, means decreasing the temperature of said element at a predetermined time, said element being so located and adjusted that its rate of cooling is in direct proportion to the amount of heat necessary to raise the building temperature to normal, and means responsive to the rate of cooling of said element f r controlling the heating means and for deter ining the length of time that the heating means must be operated in order to restore the temperature of the building to normal at the predetermined time.

9. In a system of the class described, the combination of heating means for a building, means for controlling the heating means to maintain the building temperature normal for a predetermined period and to permit the building temperature to deviate from normal at the end of said period, means to control the heating means to cause the temperature to be restored to normal at a predetermined time, said last mentioned means including an element capable of being heated, means for heating said element to a maximum temperature during the time that the temperature is permitted to deviate from normal, said element being subject to outside temperature, wind and solar radiation and so designed that its rate of cooling will be in direct proportion to the amount of heat necessary to raise the building temperature to normal, means to permit the temperature of said element to decrease at a predetermined time, and means for causing operation of the building heating means at a time thereafter which is dependent upon the rate of cooling of the element so that continuous operation of the heating means will cause the temperature of the building to be restored to normal at said predetermined time.

10. In a system of the class described, the combination of heating means for a building, temperature responsive means in control of the heating means to maintain the temperature of the building normal during predetermined periods, means interrupting control over the heating means by said temperature responsive means during other periods whereby the building temperature is allowed to drop below normal, means for causing uninterrupted operation of the heating means at the end of said other periods, and means for determining the time that said uninterrupted operation of the heating means is initiated so that the temperature of the building will be at its normal value at the beginning of said predetermined periods, said last mentioned means including a heat retaining element, means heating said element to a temperature higher than that of the ambient atmosphere during said other periods, means operative to permit the temperature of said element to decrease after a predetermined time interval prior to the expiration of said other periods, said element being so located and adjusted that its rate of cooling is in direct proportion to the heating load on the building, and means responsive to the rate of cooling of the element for initiating operation of said heating means,

11. In a system of the class described, the combination of heating means for a building, temperature responsive means in control of the heating means to maintain the temperature of the building normal during predetermined periods, means interrupting control over the heating means by said temperature responsive means during other periods whereby the building temperature is allowed to drop below normal, means for causing uninterrupted operation of the heating means at the end of said other periods, and

means for determining the time that said uninterrupted operation of the heating means is initiated so that the temperature of the building will be at its normal value at the beginning of said predetermined periods, said last mentioned means including a thermostatic means, means for heating said thermostatic means to a predetermined temperature during said other periods, means for decreasing the heating of said thermostatic means at a predetermined time interval prior to the expiration of said other periods, said thermostatic means being so located and adjusted that its rate of cooling is in direct proportion 

